TRENTON, N.J. (AP / CBS 2 / WCBS 880) – Gov. Chris Christie, who halted construction last month on a new commuter rail tunnel between New Jersey and New York City, said Monday that he would consider contributing to a cheaper alternative: extending New York’s No. 7 subway line under the Hudson River to New Jersey.

Speaking on Millennium Radio’s “Ask the Governor” program Monday night, Christie said extending the No. 7 line from Manhattan through Hoboken and onto Secaucus is ‘a much better idea” than the tunnel that was the nation’s most expensive public works project.

Christie scrapped that project because of potential cost overruns, forfeiting $3 billion in federal funds that had been approved. New Jersey could be on the hook to repay the federal government $350 million already spent.

Christie said he hadn’t yet spoken with New York Mayor Michael Bloomberg about the proposal. Policymakers in Bloomberg’s office have been discussing whether it would be possible to extend the line.

“This is an example of what can happen when you decide to take a strong, principled stand on something,” Christie said. “If something is necessary, people find other ideas that are more equitable.”

Christie said the proposed subway extension has three points in its favor: It would be cheaper than the scrapped tunnel, it would connect to Penn Station and Grand Central Station and would have funding from New York City and state.

He then chided Sen. Frank Lautenberg for not speaking up on behalf of the new idea. Lautenberg helped secure federal funding for the rail tunnel.

The $8.7 billion project to construct a second rail tunnel between New Jersey and New York was 15 years in the making when Christie killed it Oct. 27. Former Gov. Jon Corzine broke ground on the project amid his re-election campaign against Christie. Christie later accused the former governor of rushing the start of the project for political gain; Corzine said he was creating jobs.

New Jersey was expected to shoulder $2.7 billion of the costs, plus overruns. The federal government and the Port Authority of New York and New Jersey had each committed $3 billion to the project.

Before the most recent idea goes anywhere, it would need support from Christie, Bloomberg, who’s an independent, and New York Gov.-elect Andrew M. Cuomo, a Democrat. U.S. Sen. Charles E. Schumer, D-N.Y., offered his support in obtaining federal funds to make the idea work.

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